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Nanometer Ni0.5Zn0.5Fe2O4 powders with spinel phase were prepared by the hydrothermal method using purified FeSO4 solution from sodium jarosite's slag as materials. The results show that the spinel phase of Ni0.5Zn0.5Fe2O4 powders begins to form at a relatively low temperature (130 ℃) and a shorter holding time (1 h) when pH=8. The crystallization kinetics equation at 200℃ is ln[-ln(1-x)] =-0.78+0.951n t. The growth activation energy of Ni0.5Zn0.5Fe2O4 grains is 41.6 kJ/moL in hydrothermal synthesis process. With the increase of sintering temperature, the density and diameter shrinkage of ferrite circulus increase, whereas its pores decrease. The results of magnetic measurements show that saturation magnetic flux density Bs increases and the coercivity Hc decreases with the increase of their sintering temperature. Magnetic parameters of all the investigated samples satisfy the character demand of high Bs, low Br and low Hc of soft magnetic ferrite materials. 相似文献
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采用硫铁精矿作还原剂还原硫铁矿烧渣酸浸液(硫酸铁),并用沉淀法从硫酸亚铁溶液制备α-Fe2O3。实验结果表明:当硫酸铁溶液中Fe^3+浓度为1.1mol/L时,在液固比为3:2,温度为90℃,搅拌速度500r/min的条件下,反应3h,硫酸铁溶液中Fe^3+的还原率达到96.5%,其反应级数为1.66级,表观活化能为60.26kJ/mol。还原后得到的硫酸亚铁经过净化除杂,滴加到含有适量有机添加剂的沉淀剂NK4OH-NH4HCO3中,沉淀洗涤干燥后900℃煅烧2h,煅烧产品再用稀硝酸和氢氟酸洗涤,得到高纯球形α-Fe2O3。 相似文献
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从硫酸溶液中还原制取金属碲粉 总被引:2,自引:0,他引:2
采用SO2作还原剂从含碲的硫酸溶液中制取碲粉,并确定了SO2从硫酸溶液中还原碲的最佳条件:反应温度80℃,NaCl浓度1.2 mol/L,SO2流量0.1 m3/h,反应时间40 min,碲的还原率达到99.63%。还原所得粗碲粉经亚硫酸钠脱硒,盐酸酸洗除杂处理,硒、砷、锡、铜的脱出率分别达到99%、93%、80%、87.5%,得到含碲99.669%的金属碲粉。XRD和SEM表征表明还原碲粉的形态为针状晶体。 相似文献
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通过对金川公司第一冶炼厂闪速熔炼系统贫化电炉处理外购铜矿石作硫化剂工业试验结果的分析,阐述了原料中的铅、锌在闪速熔炼系统分布与走向。并据此提出系统处理含铅、锌原料的建议。 相似文献
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1 INTRODUCTIONOwing to low mass , high strength and easymachining, aluminum ( Al) and its alloys havebeen widely appliedin many fields .But the chemi-cal character of Al is very active ,it can be oxidizedeasilyinthe at mosphere and erodedinthe foul con-dition,and its wear resistance is poor . All theseseriously affect its application andlifeti me .It is aneffective protective measure to i mprove perform-ance by means of plating alloy on Al substrate .Ni-Cr alloys have many characteristi… 相似文献
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电沉积Fe-Ni合金箔的工艺和性能研究 总被引:2,自引:0,他引:2
用电沉积的方法,在N iSO4及FeSO4电解质体系中成功制得了铁的质量分数为23.2%~63%,厚度为23~43μm的Fe-N i纳米晶合金箔。镀层光亮平滑,内应力小,有优良的韧性和耐腐蚀性。镀层中铁含量及电流效率随着电流密度、pH、温度的变化而变化。电流密度、溶液温度和pH影响合金箔的沉积速度和硬度;合金箔中的Fe含量影响合金箔的耐腐蚀性。应用X-射线衍射来测量晶格常数和晶粒粒径的大小,用扫描电镜观测镀层的表面形貌。硬度为16.8~19.5HR 30T,抗拉强度和延伸率分别为779.66 M Pa和1%,电阻率为29.56~62.99(μΩ.cm)。 相似文献
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火焰原子吸收光度法测定含铅碲渣样中碲的研究 总被引:2,自引:0,他引:2
建立了酒石酸-硝酸酸溶处理样品,在王水-酒石酸介质中,不必进行预分离,采用空气-乙炔火焰原子吸收分光光度法直接测定铅碲渣中的碲。研究了灯电流、乙炔流量、燃烧器高度、溶液介质条件及酸度等有关工作条件。碲浓度在1~16μg.ml-1范围内与吸光度As有良好的线性关系,其回归方程为A=0.02075c+0.00138,相关系数0.9999,特征浓度0.21μg.ml-1,检出限0.09μg.ml-1。本方法用于铅碲渣中碲的测定,回收率为98.0%~102.3%,相对标准偏差为0.4%~0.8%。 相似文献